The ongoing Program Project on the Economics of Aging is a coordinated series of investigations that analyze the economic circumstances and health care of the elderly. It addresses issues that are particular importance to the well-being of individuals as they age and to a society at large that will be composed increasingly of older persons. By addressing simultaneously several important and interrelated issues, the aim is to achieve a better understanding of aged than would emerge from separate research efforts. A unified approach with aging as a focus can lead to a whole substantially greater than the sum of its parts. The program project will continue to be coordinate through an administrative and support core, and will be composed of a data acquisition core together with eight subprojects: (1) financial status one, (2) financial status two, (3) subjective beliefs and saving, (4) wealth, health, and differential mortality, (5) aging and saving in developed and developing countries, (6) international comparisons, (7) firm health care, and (8) Medicare expenditure growth. As in the work to date, the selection of new research topics has been guided by the questions that in the judgment of the research group will be of primary and increasing concern with an aging population. In addition to the principal investigator and the other senior investigators, each of the subprojects will involve a small number of key personnel, for whom funding is requested. This group will form the central research team. The overall work of the National Bureau of Economic Research on the economics of aging, however, will involve a considerably larger group. The coherence of the project is assured through many small-group meetings in Cambridge, summer institutes, formal conferences, and informal subproject meetings. An important goal of the project is to attract younger faculty and graduate students to research on the economics of aging. The project will direct a great deal of research talent to the economics of aging over the next several years. In addition, the project will leave in its wake a large number of economists who are well-versed in the economic, health, and social problems of the elderly and who will in turn encourage graduate students and others to direct their attention to these issues.